The present invention relates to a profile-connecting device for connecting two profile bars, in particular made of light metal, of which a first profile bar has an end side butting against a longitudinal side of a second profile bar, at least that outer longitudinal side of the second profile bar which is directed toward the end side of the first profile bar and at least one outer longitudinal side, in particular two mutually opposite outer longitudinal sides, of the first profile bar having an undercut groove.
Such profile bars, in particular in the form of aluminum profile bars, with outer grooves are frequently joined together in the industrial sector to form load-bearing structures for equipment.
For the assembly of aluminum profiles, a number of connections in the case of which at least one profile, in some cases both profiles, have to be machined, i.e. provided with bores or milled recesses, are known. In addition to the machining costs, the profile elements provided are often difficult and thus expensive to produce.
In addition, the profile machining usually weakens the strength of the profiles precisely in the connection region. In the case of some of the known connections, the tightening or connecting moment is non-uniform and thus is not optimum.
The self-tapping screws used for a fair number of profile-connecting devices shift the machining problem to the assembly stage.
EP-B1-0 460 360 discloses a profile-connecting device of the type mentioned in the introduction. In this case, a flange is connected to at least one sliding block, which is screwed in an inner chamber of the first profile bar via a screw. In the axial direction of the groove of the first profile bar, the flange is then screwed, via a screw-connection element, to sliding blocks arranged in the groove of the second profile bar.
EP-0 233 525 also discloses a profile-connecting device which uses a flange which is screwed in the inner chamber of the first profile via a screw, an arresting part having been introduced in the inner chamber beforehand and secured there in a form-fitting and/or force-fitting manner.
Taking the abovementioned prior art as the departure point, the technical problem or the object on which the present invention is based is to avoid the disadvantages specified in the prior art and to specify a profile connector which ensures a stable connection between the profiles with a uniform tightening or retaining moment without any machining of the profiles. An additional intention is to allow quick installation of the connection, which can be introduced directly in the connection region without preliminary machining of the profiles being necessary.
A further technical problem is to specify a profile-connecting device which can also be introduced subsequently into an existing structure without the existing structure having to be dismantled.
The profile-connecting device according to the invention is provided by the features of independent claim 1. Advantageous configurations and developments form the subject matter of the dependent claims.
Accordingly, the profile-connecting device according to the invention of the type mentioned in the introduction is characterized by a clamping unit which, at least in certain regions, has an outer contour which can be clamped in the groove by virtue of being widened, a screw unit which can be introduced into a continuous cutout of the clamping unit, and a threaded unit which can be introduced with rear-engagement action into the groove of the second profile bar, the clamping unit being spread apart, and thus clamped in the groove of the first profile bar, by virtue of the screw unit, which is introduced into the clamping unit, being screwed into the threaded unit, and a partially clamping and partially form-fitting connection between the two profile bars being produced in conjunction with the threaded unit, via the screw unit.
A particularly advantageous development of the profile-connecting device according to the invention is distinguished in that the screw unit is designed as a wedge screw with flanks which are inclined in certain regions, and the clamping unit has correspondingly inclined mating flank regions, a particularly advantageous configuration being distinguished in that the inner contour of the mating flank regions of the clamping unit is formed with a self-locking slope, this making it possible to ensure a permanently reliable connection.
A particularly preferred alternative configuration is distinguished in that the clamping unit has a base plate with a width which corresponds to the groove width of the profile bar, and at least two clamping elements, which can be spread apart by the threaded unit, are integrally formed on the base plate, flush with the outside of the latter, with the result that, in the non-spread-apart state, the clamping unit can be pushed at least into the groove of the first profile bar and/or, in certain regions, into the groove of the second profile bar. Since the clamping unit has the same width as the groove of the profile bar, screwing the screw unit into the threaded unit, in addition to the spreading action, causes the profiles to be centered automatically as soon as the screw connection engages with the threaded unit, which may preferably be a hammer nut.
A configuration which is particularly preferred in terms of production and straightforward handling is distinguished in that the clamping elements each have a shoulder which, in the inserted and spread-apart state of the clamping unit, engages, at least in certain regions, behind the groove of the first profile bar, and, in one development, the shoulder depth increases from the base plate to the opposite end region of the clamping elements, that is to say it is possible to set a very high clamping pressure, when the clamping unit is spread apart, in the regions adjoining the base plate.
The regions which, in the inserted and spread-apart state, butt against the groove wall within the opening width contain knurling, as a result of which the clamping force can be reliably increased.
A possible material for the clamping unit and/or centering unit is preferably an aluminum/zinc pressure die casting or steel.
The clamping unit and/or centering unit may also be in the form of a precision forging.
As the threaded unit, use is preferably made of a hammer nut or of a sliding block, in particular a spring-activated sliding block.
A configuration which is advantageous particularly in terms of the connection forces and moments transmitted is distinguished in that in each case one clamping unit with centering and screw unit is arranged in the two mutually opposite grooves of the first profile unit, the screw unit being screwed into in each case one threaded unit or, alternatively, into a common threaded unit, which has two bores corresponding to the spacing between the two grooves.
Straightforward and quick installation is further assisted, in an advantageous configuration, in that the screw unit, on the top side, has a contour for the engagement of a tool, which contour is preferably in the form of a polygonal socket contour.
Further embodiments and advantages of the invention can be gathered from the features additionally given in the claims and from the exemplary embodiments specified hereinbelow. The features of the claims may be combined with one another in any desired manner provided that they are not obviously mutually exclusive.